A plenoptic camera acquires light field data (multi-viewpoint image group) representing the positions and angle information of light beams. When the light field data is used, it is possible to adjust the focus position after imaging, change the viewpoint position, and acquire the distance to an object. This technique is known as computational photography. As a method of encoding or decoding light field data (multi-viewpoint image group) captured by a plenoptic camera, a method of JPEG-encoding a specific viewpoint and LZ-encoding the remaining viewpoints is known. A literature that discloses the technique is Japanese Patent No. 4969474.
The light field data captured by the plenoptic camera is preferably held in a small data amount. In addition, it is preferable to efficiently hold the data to cope with various processing requests from the user for refocus processing (adjusting the focus position after imaging), depth estimation processing, stereo vision, naked eye stereo vision, and the like. In a conventional method, a refocus image or a depth map is generated in advance from light field data, and the generated data is output in accordance with a processing request from the user. However, since the data are generated in advance, the amount of held data increases. In another method, light field data is encoded, and data is generated by decoding the light field data in accordance with a processing request from the user. However, since data generation is performed by decoding the light field data for each processing request from the user, the processing load increases. That is, there is demanded a light field data encoding method capable of quickly coping with various processing requests from a user.